Computing machine



March 26, 1946. B. D, SMITH 2,397,166

COMPUTING MACHINE Filed March 23, 1943 4 Sheets-Sheet 1 INVENTOR.

- 3.051211%! BY M W4 ATTOKNEYJ March 26, 1946. SMITH 2,397,165

COMPUTING MACHINE Filed March 25, 1945 4 Sheets-Sheet 5 INVENTOR.

BY -fi. D. 512M510 ym d QQIZQQ/ ATTORNEYS March 26, 1946. B. D. SMITH ,397, 6

COMPUTING MACHINE Filed March 23, 1943 4 Sheets-Sheet 4 IN VENTOR.

ATTORNEYS Patented Mar. 26, 1946 UNITED STATES [PATENT OFFICE 2,397,166 comu'rmc momma Blanchard D. Smith, Atlanta, Ga., assignor to Scripto Manufacturing Company, Atlanta, Ga., a corporation of Georgia Application March 23, 1943, Serial No. 480,221

7 Claims. (01. 235-145) The invention relates to computing machines and has as an object the provision of an improved type of mechanism for computing machines shown as adapted to an adding machine, and of an improvement in keyboards for computing machines.

It is an object of the invention to secure compactness to such an extent that, when embodied as an adding machine the overall dimensions shall be roughly one-half of the dimensions of existing machines which secure the same functions.

Further objects of the invention are: to provide a keyboard for computing machines generally wherein the individual keys are substantially onehalfthe size of usual keys and are constructed and arranged for operation two at a time in order to provide finger space for depression of the desired key;

To provide for very simple assembly;

To provide computing machine mechanism actuated one-half by forward movement of an actuating element and the remaining half by return movement of the said element whereby movement is reduced and space conserved;

To provide a computing machine so constructed as to be possible of manufacture very largely from plastic and the necessary metal parts of which involve very little machining;

To provide a novel form of carry one mechanism.

Further objects of the invention will appear from the following description when read in connection with the accompanying drawings showing illustrative embodiments of the invention, and wherein:

Figure l is a vertical section on broken line of Figure 2;

Fig. 2 is a detail plan view with a portion of the cover broken away;

Fig. 3 is a detail vertical section on line 3-3 of Figure 2;

Fig. 4 is a detail vertical section on line 4-4 of Figure 2 partly in elevation;

Fig. 5 is a detail section on line of Figure 2 showing two keys depressed;

Fig. 6 is a detail plan view of certain keys illustrating an alternative key structure;

Fig. 'I is a section similar to Figure 4, taken on line 1-1 of Figure 6;

Fig. 8 is a detail section on line 8-8 of Figure 1 with parts omitted;

Fig. 9 is a detail section on line 9--9 of Figure 8; and

Fig. 10 is a detail section on line ||l-||l of Figure 1.

As shown the device comprises a base plate l5 carrying a plurality of posts l5, one for each key, the posts being arranged in rows of nine each in accordance with the usual arrangement of keys of computing machines. As shown the posts I6 are cast integral with the base I5 and for conservation of material as well as to house springs H, the posts are formed hollow. The springs Il may be retained in the posts by strips |8 carried by the bottom of the plate, and to support the keys l9, 2|, 23 are shown as formed with an end 60 projecting through slots 6| in the posts l6.

Slidable between the posts and guided thereby there are shown a plurality of keys l9, which keys are semi-circular at opposite sides thereof to fit between the posts. Carried by each key there is shown a stop member 20, for a purpose to be described. The key 2| for numeral 1 of each row is roughly one-half of the keys l9 and this key 2| carries a stop member 22. The key 23 for the numeral 9 has one complete cylindrical opening 24 as well as a half cylinder 25, the latter to coact with the 8 post. Other than the keys 2| and 23, the remaining keys are interchangeable with each other.

As shown in the form of the invention of Figure 2 the numeral is carried by the top of the post and is visible not only in the space between the keys l9, 2|, and 23, but it is intended to form the keys of transparent plastic whereby the light may have ready access to the posts and the numerals thereon as well as providing that these shall be readable through the keys, and that the keys shall not cast shadows on the numerals.

The tops of the posts l6 are of such a size that the spacing between their centers is substantially one-half of that of the usual keys of a computing machine, therefore when the mechanism is to be operated for the integer 1 the finger will contact both keys 2| and I9 and when any other integer is wanted and the finger is pressed over the corresponding indicia upon the top of the post two keys will be depressed. The circular space between these two keys will have much the effect and feel of the usual depression in the surface of a typewriter key.

Actuated by the keys upon their depression there is shown a plurality of rack bars 26, one

7 for each row of keys, which rack bar is moved.

forwardly by depression of the key and is stopped by contact of a member 21 carried b the rack bar which comes into contact with the stop 20 corresponding to the lowest numeral whose key is depressed.

To actuate the rack bars 26 there is shown a rod 28 passing along each row of posts below a notch 29 in each of the keys, as clearly shown in Figure 4. For coaction with the rod 28 the posts are, as shown in Figures 4 and 8, flattened at one side as at 30. The rod 28 is as shown anchored at its rear end in a plate 3|, in the manner best shown in Figure 10, wherein the plate 3| is formed with a slot 32 to allow the rod to be depressed, the rod being held in the upper end oi. the slot by means of a spring At its ion ward end the rod 28 is formed into a bell crank arm 34.

The arm 34 has its end 35 turned at an angle and pivoted in a plate '36 which extends across the base i to support the ends of all of the rods 8 of the machine. Coiled about the end 35 is a spring 37 having one end lit acting on the arm 34 and the other end anchored to the base 39 of the plate 36. The torsion of the spring 3i is just sufficient to support the weight imposed on it, and to actuate its rack bar for return movement.

Mounted on the rod is a block til in which there is pivoted an ed M of a crank having an arm 22, shaft portion and an arm M, the end of the latter being turned at an angle and entering a block t5 carried by the corresponding rack bar it.

The shaft portion 33 or the last described bell crank is pivoted at two points in springs t6 which, as shown in Figure 8, are portions of a comb plate il secured to the base 85 by screws iii which also secure in place the angle shaped plate The margin it of plate all is shown as turned downwardly and engaged in a groove in the base 85.

As shown in Figure 9 the portion 5b of the base it under the springs as is thinner than the portion 5i toward the end of the base. Below the spring members 46 the base is cut away upon an angle as indicated at 52 in Figure 9 to allow for the depression of the springs 36, the spring ac-= tion being stiffened by support of the members 53 between the spring portions.

When any keys are depressed the first action that takes place is the yielding of the springs 65 by pressure exerted upon the shaft 43 by means of block 40. This lowers the rack 26 causing the lower rack teeth of the bifurcated end of t e rack bar to leave the lower teeth of pinion 55, which teeth are, however, not freed until the upper rack bar comes into engagement with the upper teeth thereof.

Further depression of the rod 28 then causes 46 revolution of the shaft 43 with resulant motion further to the right in Figure l of the rack bar causing the revolution of the pinion 54 an amount equal to one-half of the integer represented by the lowest key depressed and upon release of the keys the spring 31 causes return of the rack bar to complete the necessary revolution of the pinion 54.

It will be seen that beginning at the left of Figure 1 the members 21 are successively each one integer further spaced from the stop with which they are to coact when the keys are depressed so that when the last key 20 to the right in Figure 1 is depressed the upper rack teeth will move forwardly a distance to actuate four'of the teeth 54 before the rack bar is stopped by the stop member which is depressed by the number 8 key. No ratchet tooth or stop member is necessary for the 9 key as that will be operated by the full motion of the rack bar equivalent to 4 /2 gear teeth, the returning movement of the rack bar completing the actuation of nine teeth.

The upper end of the crank arm 44 will be seen to move on the arc of a circle as it swings. To preserve a substantially straight line motion, and to guide the rear end of the rack bars, a stationary rod 56 is provided extending crosswise of the machine and through all of the rack bars, the rack bars being formed each with a slot 61 to slide upon rods 56, which slot'is as shown arcuate asemee in shape to cause the rear end of the rack bars to rise to follow the swinging motion of the bell crank.

The mechanical action oi the rod 28 is a combination of crank action and or a lever of the third class. To compensat for spring of the rod when the power is applied close to the fulcrum of the lever, the fulcrum is provided in the form of spring 33 and the crank end 62 of rod- 28 is movable in slot 32 as best shown in Figure 10, and as already described.

The number adding and registering. mecm comprises a series of devices shown in detail in Figures 1, 2 and 3 as mounted on a fined station= ary shaft bib For numerals of each order there is shown a pinion ti l having eighteen teeth 54 which. ccact with the rack teeth 38 already referred to. The pinion lid is mounted on a sleeve 65 revoluble on the rod. The mechanism further comprises a number wheel 96 for each number, shown as hearing two sets of numerals from 0 to 9 visible through the openings 56 in the cover 81.

To couple the pinion with the number wheel there is shown a coupling disk 66 formed with twenty projections ten of which project toward the pinionand extend between the teeth 54 as at 69, and the remaining ten project toward the number wheel and are loosely received respectively in ten openings it, as at "M. The disk of coupling member lid is shown as rigidly carried by an eccentric portion '82 of the sleeve 65. The eccentricity of the mount of the coupling is such that but one or two of the members 69 are between and in operative engagement with the teeth of the pinion at any one time, as indicated in Figure l. The number wheel 96 will therefore be driven positively by the pinion through the coupler, but if the drive is from the coupler moving relative to the pinion, each half revolution of the sleeve, due to the differenc between the number of the teeth in the pinion and the number of themembers 69, will cause the number wheel to advance one numeral.

A "carry one device is shown as comprising a. plate member '13 revoluble on shaft 63 and driv. ing sleeve 65 through projections 14 from the end of the sleeve, entering openings in the plate. To cause rotation of the plate a spring in the form of a flat helix is shown, its outer turn anchored to the number wheel and its inner turn anchored to two lips 16 projecting from the plate. The spring 15 is given a moderate degree of pre-winding when the device is assembled and is additionally tensed by the adding movement of the number wheel. When the parts are in the position shown in Figure 3, the tendency of the plate 13 to rotate under urge of the spring is restrained by contact of an end of the plate with a stop 11.

To release the plate 13 for rotary movement a cam member 18 is carried by the rim of the number wheel at the 0" position which forces the end of plate 13 laterally out of contact with the stop H. The end surface of the hub the pinion 64 is shown. as tapered or rounded to permit movement laterally of the plate. Normally both ends of the plate 13 stand so close to the rim of the number wheel that the plate cannot escape from the stop 11. To permit the end of the plate 13 opposite the stop 11, to move toward the number wheel when the remaining end is moved therefrom by the cam 18, a notch 80 is formed'inthe rim of the wheel. one cam 18 and notch 80 in the number wheel, the plate is released by pressure upon opposite ends alternately.

There being i The tension on the springs 15 in each of the number wheels of the device would cause revolution of the wheels except for engagement of the teeth of the pinions with the rack teeth of bar 26, in the case of wheels advanced from zero, or except for contact of the straight face of the cams 18 of wheels at the position. To clear the machine it is therefore only necessary to move the rack bars laterally from the pinions. To provide for this movement the rack bars 26 are shown as each contacting an abutment 8| carried by rod 56, the bars each being pressed toward the abutment, the keys I9 and the pinions-forwardly of the abutments by springs 82 mounted on the rod 56 in the manner shown in Figure l, and reacting against second abutments 83 carried by the rod.

To simultaneously move the rear ends of all bars to the left in Figure 2 in order to move the racks thereof to the right clear of the pinions, there is shown a plate 84 loosely mounted on pins 85, 86 by means of diagonal slots 81, 88, as shown in Figure 10. As illustrated the pin 85 is fast in plate 84 and works in slot 81 in plate 3|, while pin 86 is fast in plate 3| and its slot 88 is formed in plate 84. A tension spring 89 reacts between plates 8| and 84 to hold each pin at an end of its slot. Wings 90, 9| are shown projecting from plate 84 through notches 92 in plate 3| and standing at opposite sides of the rear ends of each rack bar. Pressure upon clear key 93, w l cause lateral movement of plate 84, wings 90 and therefore of the rear ends of the rack bars thus throwing the forward ends clear of the pinion allowing each number wheel to be revolved to the zero position.

When the number wheels are freed from control of the rack teeth of bars 26, to clear the machine, the number wheels will be revolved by springs 15 until at zero position the flat sides of cams 1.8 strike the plates 13. To prevent further movement by yielding of plates 73, light leaf springs 8| are provided, which springs are depressed by the ends of the plates during carry-one movement thereof.

A slightly difierent form of key is shown in Figures 6 and 7 wherein they are formed with semi-circular webs 94 which closely approach the similar webs of adjacent keys. In this structure the numerals instead of being carried by the tops of the posts, are shown as carried, one-half of each by adjacent webs.

The cover 6'! is shown as formed with the windows 66, with elongated slots 95 through which the keys project, with an opening for clear key 93, and may be held to the base I in any convenient manner.

The size and spacing of key operated machines is determined by the size of the human finger and the distance between centers of the keys must accommodate all but abnormal fingers. The usual distance between such centers, if drawn to the same scale as Figure 2 of the drawings herein is indicated by the dot-dash circles on that figure, the figure being drawn to a scale greater than the actual size of the device. Finger-tipsize as used in the appended claims denotes this usual spacing of the keys in known key operated machines. For purposes of illustration the size and spacing of the keys is shown as onehalf finger-tip-size but it is apparent some other fractional part of the normal size could be utilized.

In the operation of adding machines of the usual size it is necessary to move the upper arm in order to depress the keys in the upper half of the keyboard. It is much less tiring if the operator can rest the elbow on the table and reach the necessary keys by a wrist and forearm movement. Therefore, operators are taught to use only the lower numeral keys actuating 5 and 4 for 9 and 5 and 3 or 4 and 4 for 8, etc.

With the machine of the present invention the entire keyboard may be reached with purely wrist or wrist and forearm movement. The elimination of a mental calculation improves accuracy, and saves half the manipulating time of the operator on adding the larger numerals.

The reduction in size resulting from the improvement in keyboards with the improvement in operating mechanism enables the provision of a machine that may be easily carried in a usual coat side pocket.

Minor changes may be made within the scope of the appended claims without departing from the spirit of the invention.

I claim:

l. A keyboard for computing machines comprising: upstanding key guides spaced on centers separated a distance of substantially one-half finger-tip size; keys each comprising two connected oppositely open-sided shells each shell partially embracing one of two adjacent guides; and indicating numerals centered between each two adjacent keys.

2. The combination of claim 1 wherein the numerals are carried by the ends of said guides.

3. The combination of claim 1 wherein said shells are each upwardly closed by a web, and the numerals are carried, one-half of each by adjacent webs which form a finger-contacting surface.

4. The combination of claim 1 wherein the upper ends of said shells are open and the numerals are carried by the exposed ends of the guides.

5. A keyboard for key-actuated machines for use of adult operators, comprising: a plurality of rows of keys spaced not substantially more than one-half finger-tip clearance apart in each row; at least a portion of each key having only operating clearance from a portion of an adjacent key; indicating characters for said keys; said indicia, intermediate the first and last key of each row, common to two of said keys.

6. A keyboard for key-actuated machines for use of adult operators, comprising: upstanding key guides spaced on centers separated a distance of substantially one-half finger-tip size; keys each comprising two connected and oppositely extending guide members, each member slidably engaging one oi. two adjacent key guides; and indicating characters centered between each two adjacent keys.

7. A key board for key-actuated machines for actuation by finger tips of adult operators, comprising: a plurality of rows of nine keys each; the intermediate keys of each row spaced on centers not substantially more than one-half finger tip size apart; said intermediate keys comprising finger contacting portions extending in opposite directions toward like portions of adjacent keys: indicia for said intermediate keys each common to two thereof; and guide means for said keys common to the oppositely extending portions of said finger contacting portions: whereby a finger tip pressed over said indicia will operate two acjacent keys and the total length of said rows will be substantially one-half of the length of a row of nine individually finger operated keys.

BLANCHARD D. SMITH. 

